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curtis slawson
03-20-2012, 07:29 PM
hey just put on a DG exhaust on my 85 200x.

wont run without choke on plug is really black should i down size the main jet. It has a 108 main in it atm iv tryed to raise the c clip to the 4th grove witch is lean and tryed adujst the air fuel mixture with no change to the plug still black.

run and idles good on choke but soon has you put to no choke it dies unless your driving then put to no choke and run rough & spurtter dosen`t back fire at all.

And isnt when you put a aftermarket exhaust on it should make it leaner and not make it run rich

so should i change the main jet and get something smaller.

4x4van
03-20-2012, 08:04 PM
If it was running good before the pipe, and now it will only run with the choke on, then it is now running too lean (the choke is richening it up). Smaller main jet will will make it even worse. A plug check can't really be done without a good clean WOT plug chop, and it sounds as if it won't run good enough to do that accurately.

Again, the key here is that it runs good with the choke on. The choke richens it up significantly. So that's what you need to do with the jetting; richen it up.

curtis slawson
03-20-2012, 08:18 PM
the bike was running a little lean befor the pipe swap and now the plug is pitch black. iv also tryed 110 main jet with no inprovment stock jet is 1.08.

if i drive with the choke on then shut it off& it runs but spuddders when wot and feel`s like there no power but still dont idle unless i say on the gas with no choke

the plug was light tan befor the swap now it carboned up not wet but dry black plug

i tryed to plug shop it came out carbon black plug Brand new plug and still havent heard a back fire on let of of gas

the bike ran great with stock pipe could lift it up in 4th gear

also dosnt have stock pistion has a wiseco high compressin 10.25.1

4x4van
03-20-2012, 08:26 PM
I'm telling you, it's too lean. One size larger main is likely not enough. Think about it; what does the choke do? It richens it up. If it will only keep running with the choke on, then that means it is running too lean. Sputters on the top end, no power at the top, will only run with the choke...it's too lean. In the jetted condition that it's in, you can't do an accurate plug chop.

curtis slawson
03-20-2012, 08:31 PM
ok so get bigger jet then a 110 main jet & lower the c clip niddle so it more rich too and adjust fuel mixture too

oscarmayer
03-20-2012, 09:07 PM
you said you never touched the carb at all before the pipe change???
wis the pipe you ggot new or used? if it's used, the piep could be partly plugged causing backfeed.

curtis slawson
03-20-2012, 09:13 PM
it is a used pipe

Scootertrash
03-20-2012, 11:14 PM
Curtis,
First, lets try to keep it to one thread to keep the confusion down. It's also easier to track your progress. ;)

Go here http://www.3wheelerworld.com/showthread.php/55086-Carb-Jetting-101-Terms-Tips-and-Jetting-Theory

and print out the instructions for jetting and take them out to your garage with you when you do this. It will help you learn the procedure and the results from each change you make to the system.

Is the air filter clean? When was the last time the carb was cleaned thoroughly? You may need to take the bolt out of the muffler and remove the baffle to be sure it's clean.

You need the machine to idle without the choke first before you can continue. Make sure your idle jet is clean, don't assume that it is, verify that it is. Set your pilot screw to the factory setting ('83 - 1 3/4. After '83 - 2 1/4.) Leave the 110 main jet in and set the needle to the middle groove. Put the slide back in and tighten the cover. Make sure your throttle cable is adjusted properly. Put the airbox cover back on. Start it and warm it up to operating temp in your driveway. Once it's warmed up see if you can get it to idle without the choke by using the idle speed screw on the side of the carb. If you can get it to idle then you can fine tune your pilot screw before you test ride.

Take it for a test ride and see how it runs, then follow the jetting instructions in the link above or post back here. I'm laid off and around generally most of the day, I'll check in to see if you need help.

Jetting can be frustrating. Be patient you must young Jedi!!

curtis slawson
03-21-2012, 12:09 AM
Ok thanks for the info i will try this tomrrow.I have cleaned the carb befor i put the new exhaust on air filter had just been cleaned
Curtis,
First, lets try to keep it to one thread to keep the confusion down. It's also easier to track your progress. ;)

Go here http://www.3wheelerworld.com/showthread.php/55086-Carb-Jetting-101-Terms-Tips-and-Jetting-Theory

and print out the instructions for jetting and take them out to your garage with you when you do this. It will help you learn the procedure and the results from each change you make to the system.

Is the air filter clean? When was the last time the carb was cleaned thoroughly? You may need to take the bolt out of the muffler and remove the baffle to be sure it's clean.

You need the machine to idle without the choke first before you can continue. Make sure your idle jet is clean, don't assume that it is, verify that it is. Set your pilot screw to the factory setting ('83 - 1 3/4. After '83 - 2 1/4.) Leave the 110 main jet in and set the needle to the middle groove. Put the slide back in and tighten the cover. Make sure your throttle cable is adjusted properly. Put the airbox cover back on. Start it and warm it up to operating temp in your driveway. Once it's warmed up see if you can get it to idle without the choke by using the idle speed screw on the side of the carb. If you can get it to idle then you can fine tune your pilot screw before you test ride.

Take it for a test ride and see how it runs, then follow the jetting instructions in the link above or post back here. I'm laid off and around generally most of the day, I'll check in to see if you need help.

Jetting can be frustrating. Be patient you must young Jedi!!

El Camexican
03-21-2012, 12:31 AM
For what its worth I've never seen where putting a different pipe on a decent running engine made a dramatic change the way it sounds like yours has. Being off one jet size, or needle clip height (which is usualy the most a pipe change will require) does not effect an engine the way yours seems to have been. I'll add that most stock jetting is a little rich, so a pipe often makes things run better with no added tuning. I suspect you will find something else causing this when you look close.

4x4van
03-21-2012, 09:48 AM
Aahhh...you never siad it was a "used" pipe. In fact, in you rother post, you said you got a new DG exhaust (must have meant "new to you", right?)

As Oscarmayer said, the pipe/silencer could be partly clogged up. Scootertrash has some very good info/instructions...follow them and you should be able to zero in on the problem.

El Camexican; a "good' pipe/silencer combo can easily cause a 2-jet size difference with a high performance 2-stroke, which is what I am more familiar with. But may be right in this case, considering that his bike is a 4-stroke.

Scootertrash
03-21-2012, 11:09 AM
When I put the DG on my 200S I went from a 95 main to a 100 main and my needle ended up one groove higher.

curtis slawson
03-21-2012, 12:47 PM
hey just tryed everything still dont idle with no choke should i lower the c clip one more ? cant get it to idle with no choke unless i stay on the gas & try to adjust idle screw just make when i start on choke it rev real high

rdlsz24
03-21-2012, 01:50 PM
Make sure your pilot jet is not clogged. That's the first thing I check when I can't get something to idle right. Never fails that sucker is plugged.

Rob

curtis slawson
03-21-2012, 03:01 PM
ye its not clogged i can see right therw it
Make sure your pilot jet is not clogged. That's the first thing I check when I can't get something to idle right. Never fails that sucker is plugged.

Rob

badass350x
03-21-2012, 03:12 PM
Put it back the way it was with the stock pipe and jetting and see what it does!

Scootertrash
03-21-2012, 09:05 PM
Are you referencing the manual so you are sure of what you are doing? Not trying to be a jerk, It shouldn't be this difficult, I just want to make sure you are adjusting the proper screws at the proper time..

Sounds like your idle circuit is still screwed up. I wouldn't think that the pipe would cause you to need a different pilot jet.

Are you sure your idle speed screw/throttle stop screw on the side of the carb is actually lifting the slide when you adjust it? Are you flicking the throttle as you adjust the screw to be sure it's not binding the slide? (not the pilot screw that you need to come up from underneath the carb to get at)

Otherwise you may have to do what badass350X said and put it back the way it was, make sure it runs good that way and start from there.

Dirtcrasher
03-21-2012, 09:34 PM
Leave the friggen needle alone! Get the main jet correct then fine tune the midrange with the clip position if needed (rarely necessary for the average guy), you may have a slight midrange stumble.

The main jet is most important, it all trickles down from there......

MAKE ONE JETTING CHANGE AT A TIME!!

curtis slawson
03-21-2012, 09:42 PM
yes i have been looking at the manual. The air screw dose work but has no afect on no choke but when you put on choke or half choke you can adjust the idle and work's good& iv tryed hittting the throttle still nothing but i can keep the bike running if i give it gas then shut the choke off and drive it but it very jerky and sputters on give it gas & stalls out if i let go.
The bike was working perfect befor new pipe it would idle perfect on no choke i could catwalk it in 4th gear no problem so i know it was running good befor.
Are you referencing the manual so you are sure of what you are doing? Not trying to be a jerk, It shouldn't be this difficult, I just want to make sure you are adjusting the proper screws at the proper time..

Sounds like your idle circuit is still screwed up. I wouldn't think that the pipe would cause you to need a different pilot jet.

Are you sure your idle speed screw/throttle stop screw on the side of the carb is actually lifting the slide when you adjust it? Are you flicking the throttle as you adjust the screw to be sure it's not binding the slide? (not the pilot screw that you need to come up from underneath the carb to get at)

Otherwise you may have to do what badass350X said and put it back the way it was, make sure it runs good that way and start from there.

El Camexican
03-22-2012, 02:07 AM
ye its not clogged i can see right therw it

Did you remove it? I don't know your model, but there are usualy a number of cross drilled holes that can plug up in that jet. You need to pull it out and clean them. rdlsc24z may have solved your problem.

4X4van: Good point, I was thinking 4 stroke when I made the comment.

tri again
03-22-2012, 04:27 AM
I really have no business in this thread but
if it ran good before the new (used) pipe,
maybe pipe has a rats nest in it? Collapsed rust?

Then the carb came off because that's what we're supposed to do to rejet for
the different flow.
Any chance there's a vacuum leak now?
Would a vac leak make it run lean?

I know these charts are not right for your issue but it's all I could find.
Maybe jog some memories at least, or find ones for a 4stroke.

Hey, I just spent an hr today trying to figure out why the tv wouldn't work.
It was plugged in, breakers were ok...........................
The power was out.

JJMF1979
03-22-2012, 12:04 PM
Is the throttle slide in right?

curtis slawson
03-31-2012, 12:59 AM
i have no air leaks replace intake gasket on the motor. Still dosen't run without choke run's little bit better after the new gasket but still dont run right.
was justwondering what main jet should i try 115 main jet & up and then go down from there.

Thanks im going nut's without driveing my 200x!

KASEY
03-31-2012, 01:26 AM
MAIN JET IS FOR WIDE OPEN THROTTLE.,... it has no effect on your problem,,,,, you have a clogged idle circuit .. blocked pipe or an air leak,, its that simple,, running only with the choke on is a sure sign of a fuel related problem,, and NOT THE MAIN,,,,, i like the idea of putting it back to the way it was and seeing what you get,,,,,,,,,,if it runs great,,,,,,,IT WON'T... FIND THE PROBLEM,

curtis slawson
03-31-2012, 01:37 AM
ok good to know im picking up a use 84 200x carb tomrrow see how it dose.I spayed around carb with not reving so there no air leak there pipe is good i can see light at each end nothing wrong there. Iv tryed to put it all back to stock pipe and jetting i get the samething now so maybe isussues with the carb now>?
MAIN JET IS FOR WIDE OPEN THROTTLE.,... it has no effect on your problem,,,,, you have a clogged idle circuit .. blocked pipe or an air leak,, its that simple,, running only with the choke on is a sure sign of a fuel related problem,, and NOT THE MAIN,,,,, i like the idea of putting it back to the way it was and seeing what you get,,,,,,,,,,if it runs great,,,,,,,IT WON'T... FIND THE PROBLEM,

JJMF1979
04-03-2012, 10:03 PM
So what happened with this issue curtis??

yamaha driver
04-04-2012, 08:15 AM
i would get a carb kit and rebuild it. thats what i did with mine

Husky250
04-04-2012, 01:01 PM
MAIN JET IS FOR WIDE OPEN THROTTLE.,... it has no effect on your problem,,,,, you have a clogged idle circuit .. blocked pipe or an air leak,, its that simple,, running only with the choke on is a sure sign of a fuel related problem,, and NOT THE MAIN,,,,, i like the idea of putting it back to the way it was and seeing what you get,,,,,,,,,,if it runs great,,,,,,,IT WON'T... FIND THE PROBLEM,

Was waiting to see this. Or.... if it running lean at idle (need for choke) may need a larger Pilot. On my TTR with a new pipe, I have to go up on the pilot before I could even do a plug test. (Yes it's running like a champ now)

GO OVRIT
04-04-2012, 05:10 PM
Whats your method of cleaning the carb. Some you can just use a can of quality carb cleaner and some compressed air, but a lot of times you can't get around soaking the carb.

Erics350x
04-04-2012, 08:16 PM
adjust the mixture screw out about 1 turn and see what happens